Many online and offline reading applications allow users to read documents (e.g., articles, works of fiction, textbooks, newspapers, magazines, etc.) on a screen. However, studies have shown that, during a normal reading process of an untrained reader, the movement of the eyes of the reader is not a smooth straight line across a line of text from left to right. Rather than that, readers typically go back to read (consciously read-back) and jump back to read (subconsciously read-back) by re-reading a portion of text already read, and this re-reading can consume 30% of total reading time.
Accordingly, it is desirable to provide new mechanisms for guiding user reading on a screen.